The general area of interest of the presently proposed research is the behavioral effects of brain injury and in particular the recovery of specific preoperative behaviors which are disrupted by neocortical insult. The theoretical position underlying the proposed research is that recovery of function occurs, when it occurs, because the neural mechanisms responsible for the disrupted behavior were spared by the neural insult. From this point, there are two major purposes of the present research. First we wish to define the nature of the behavioral deficit given that the neural systems responsible for the disrupted behavior are spared. Specifically, we propose to test the notion that the behavioral deficit occurs, vis a vis sparing, because the brain injured individual initially attempts to compensate. We postulate that this attempt to compensate represents an attempt to learn alternate ways to attain goals which do not involve the neural systems affected by the neural insult. Since the neural systems affected by the lesion are thus avoided by the injured individual, what is spared cannot influence behavior and recovery cannot occur -- i.e. there is a behavioral deficit. The second purpose of the present proposal is to define some of the parameters of both the preoperative and postoperative behavioral situations which might potentiate the postoperative participation of spared neural mechanisms. The major thrust of this portion of the research is to define what may increase the postoperative availability of spared neural mechanisms to allow their utilization and thereby facilitate recovery of function. Throughout the proposed research program we will use rats and the disruption of preoperatively learned brightness discriminations by striate ablation to model recovery of function.